Physics: Waves Flashcards
what do waves do
waves transfer energy
what is amplitude
displacement from undisturbed position to crest
what is wavelength
distance between the same point on two adjacent waves
what is the trough
the turning point of the wave back up
what is the crest
the peak of the wave where it comes back down
describe a transverse wave
the oscillations are perpendicular to the direction of energy transfer
describe a longitudinal wave
the oscillations are parallel to the direction of energy transfer
what is the wave speed equation
v (wave speed) = f(frequency) x λ (wavelength)
what three hings can all waves be
absorbed, transmitted, reflected
what is the normal
imaginary line that is perpendicular to the surface of the object at the point of incidence
what is the angle of incidence
angle between the incoming wave and the normal
what is angle of reflection
angle between the reflected wave and the normal
what is the angle rule
angle of incidence = angle of reflection
what 4 things do all EM waves have incommon
All EM waves are transverse, emitted from one source then absorbed or reflected by another, travel at the speed of light, can travel through air or a vacuum
what are the seven EM waves in ascending frequency
Radio Waves, Microwaves, Infrared, Visible light, Ultra Violet, X-Rays, Gamma Rays
what are radio waves used for
Communication
what are microwaves used for
satellite communication and cooking
what are infrared waves used for
increase or monitor temperature
what is visible light used for
transmit data in fibre optic cables
what can UV waves do
give you a tan
what are X-Rays and Gamma rays used for
radiography and medical tracers
what is the risk of EM waves
The EM radiation can be harmful to people
what are the two types of lenses
convex and concave
what do convex lens do to rays
bend the light towards the normal
what do concave lens do to rays
bend light away from the normal
what two images can lenses produce
virtual and real
what four other words can be used to describe an image
upright, inverted, magnified, diminished
what is the magnification equation
magnification = image height / object height
what do colour and transparency f visible light depend on
Absorbed wavelengths
what does every object do (infrared radiation)
emit and absorb it
what surface is the best emitter of infrared
matte black
what surface is the best absorber of infrared
matte black
what surface is the best reflecter of infrared
shiny white
what type of wave is sound wave
longitudinal wave
what causes sound waves
vibrating objects
how does the ear work
the ear drum vibrates and passes these vibrations onto tiny bones called ossicles to the cochlea. The cochlea converts these vibrations into electrical signals and passes them onto the brain
what frequency are sound waves
20Hz - 20000Hz
what is ultrasound
sound wave with a frequency above 20000Hz
what is ultrasound used for
viewing fetus in a pregnant women and destroying kidney stones
